next, a house hearing on oxygen problems on ba'ath-22 is -- f- 22's. retired general gregory martin says researchers are unable to determine specific cause as to why f-22 pilots were experiencing -- while in flight. there was a hearing about the fight to jap lost oxygen issues. the report outlines ways to reduce risk. >> the hearing will come to order. f-22 pilot physiological issues. the committee's concerns include the impact of these issues to the pilots. and the operational capability of these valuable aircraft. the committee also remains concerned that after the study of the issue, we need to understand what the level of competency is. their 06 f-22 and physiological and -- there were six f-22 physiological instances. in may of 2011, the secretary of the airforce directed the scientific advisory board and make recommendations to address concerns. for may-september of last year, there was an upward trend and reports of physiological instances. they did not determine a cause. however, the board did make findings and recommendations. the concluded th